Totally strange annomally

[paladin06]

So I parked my road runner and all the cars on the street while I cleaned the garage floor today. It was hot, 110 or so. So when I started the road runner to bring it back into the garage the fuel gauge read 1/4 tank. It read full before I parked the car outside because I filled her up this morning. Any ideas at all. Is there going to be a charge?

 

[Hemi Rebel]

Leaked, evaporated or was stolen or Gas guage sending unit malfunction. Take your pick

 

[bigmanjbmopar]

Has it cooled off yet? Check again? still 1/4 after cool? Stick a stick or something down there and manually check the level.

Here is what the inside looks like, this is not a great pic but the reflection at the center is the level of gas. The gauge read just over half.

Vent tubes from the inside, short one on the left, long on the right, so if your parked on a hill gas will rise up the long tube down hill and the short tube will be under water so to speak. so the vent line that goes through the trunk you want on the short one. ON AFTERMARKET TANKS. mine was replaced some time between 86' and 94'

What is should be per the FSM

 

[Photon440]

I'm guessing, since you didn't mention anything, that there wasn't a gassy smelling puddle under the car with a crater of dissolved asphalt, right?

 

[sleepar]

You would notice 3/4 of a tank of gas on the ground.... someone stole you're gas most likely....

 

[nm9stheham]

Parked on a slope? It is common for a guage the change some on a slope, but full to 1/4 is a lot of change.

Drive the car and see if the temp guage registers correctly; if it reads way off too, then perhaps the voltage limiter running those 2 guages has gone bad.

 

[natas33]

Too much to be evaporation, but it does happen on hot days. It is gasoline afterall.

 

[paladin06]

No leaks, no smell, not stolen..

I'm guessing, since you didn't mention anything, that there wasn't a gassy smelling puddle under the car with a crater of dissolved asphalt, right?

- - - Updated - - -

The engine temperature reads good.

Parked on a slope? It is common for a guage the change some on a slope, but full to 1/4 is a lot of change.

Drive the car and see if the temp guage registers correctly; if it reads way off too, then perhaps the voltage limiter running those 2 guages has gone bad.

- - - Updated - - -

Not stolen as the car never left my sight.

You would notice 3/4 of a tank of gas on the ground.... someone stole you're gas most likely....

 

[sleepar]

Gauge or sender.... I would try and fill it up and see what happens.... if it only holds a few gallons and is full that will tell you something.... if it takes 3/4 of a tank.... well we're all getting older and it happens....

 

[nm9stheham]

If the tank is truly full, it sounds like high resistance in the fuel sender circuit; the temp guage reading normal indicates that the 5Volt insturment voltage is right (i.e., the in-dash voltage limiter is working OK).

Do you have the ground wire on the sender on the tank to the body in-place, and are the connections clean and secure? That could do it.

Then, check the wiring connections between the dash and the fuel tank.

Then measure the sender resistance with your meter in Ohms position; it should read around 10 ohms if good and the tank is full. Remove the wire at the sender and measure between the sender's terminal and the tank body. You should get around 10 ohms with the tank full; 80-90 ohms is E.

If that is good, then the guage movement may be hanging up.

 

[bigmanjbmopar]

Did you stick a stick in there and check the level manually?

 

[paladin06]

OK, finally got to look at it since it got below 110 degrees. First the gas cap was not not fully tighten. I take the fall for that. Second the green wire to the VR was not tight. Corrected both and we are good. Thanks all.

 

[nm9stheham]

Well that was easy...good deal!

 

[paladin06]

I like easy..

Well that was easy...good deal!